Recent studies and research have been aimed at identifying new configurations of spoked wheels for bicycles leading to better performances of the wheel, as well as creating an original and innovative aesthetic effect.
Research in the field of spoked wheels for road racing bicycles has been directed to identifying increasingly important solutions that optimally reduce weight and increase the static and dynamic stability of the wheel. Research has also been directed to increasing structural strength and reduction in the risks of failure of the spokes of the wheel.
The spokes of road racing wheels make a substantial contribution to maintaining the static and dynamic stability of the bicycle wheel. Particularly in rear wheels, the spokes are responsible for transmitting the driving torque from the hub to the rim of the wheel. The driving torque transmission should occur with the maximum possible efficiency, and with minimum deformations, so as not to dissipate the energy exerted on the pedals by a cyclist. Finally, the desired results should be achieved with the minimum weight possible and without introducing risk factors for failure in the spokes. From this standpoint, a particularly critical factor is the tensioning of the spokes during wheel assembly. One of the purposes of said tensioning is to guarantee that the rim will always remain “centered” or “true”, i.e., it will not shift away from a median plane of the wheel orthogonal to the axis of the hub and equidistant from the ends of the hub itself. Thus, the spokes of a typical spoked wheel include a first set of spokes on one side of the wheel, connected to a first hub portion, and a second set of spokes on the other side of the wheel, connected to a second hub portion. The second hub portion being set at an axial distance from the first portion. Consequently, the spokes on the two sides of the wheel have an inclination or camber angle with respect to the median plane of the wheel. This inclination causes the spoke tensioning to give rise to components of force in a direction parallel to the axis of the wheel. Balancing of the components of force keeps the rim in the centered or true condition. Spoke tensioning is most critical in wheels where the spokes on the two sides of the wheel present different camber angles. This is typically the case for spokes of the rear wheel. A rear wheel hub carries at one end, a sprocket cassette. The spokes set on the side of the wheel bearing the sprocket cassette have camber angles or inclinations that are considerably smaller than the camber angles or inclinations of the spokes on the other side. Obviously, the spokes with smaller inclinations must be tensioned more than the spokes on the other side in order to guarantee the centered position of the rim. This higher tensioning gives rise to a greater risk of failure of the individual spoke itself. Different spoke camber angles on the two sides of the wheel is not unique to rear wheels. It exists in general in any wheel, whether rear or front, in which the hub is partially occupied, for instance, by the disk of a disk brake.